Improvement in rotary steam-engines



SAML. G. HALL AND GEO. W. BUGBEE, OF NORWICH, CONNECTICUT.

IlVIPROVElVlENl IN ROTARY STEAM-ENGINES.

Specification forming part of Letters Patent No. 55,092, dated May 29, 1866; antedated May 21, 1866.

To all whom it may concern Be it known that we,`SAMUEL G. HALL and GEORGE W. BUGBEE, of Norwich,in the county of New London and State of Connecticut, have invented a new and Improved Rotary Engine; and we do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in th'e art to make and use the same, reference being had to the accompanying .,(lrawings, forming part of this specification, in which- Figure l represents a transverse vertical section of this invention, taken in the plane indicated by the line m m, Fig. 2. Fig. 2 is a longitudinal vertical section of the same, the line y y, Fig. 3, indicating the plane of section. Fig. 3 is a front elevation of the same. Fig. 4 is a transverse section of the valve and its seat detached, the plane of section being indicated by the line -z z, Fig. 3. Fig. 5 is a side elevation of the same. Fig. 6 is a transverse section of the same' in the'- plane x zr', Fig. 3. Figs. 7 and 8 are sectional face views of the slides or valves detached from thepiston-wheel.

Similar letters of reference indicate like parts.

This invention relates to a rotary engine orA pump of that class in which a piston-wheel with four (more or less) slides is placed eccentrically into a stationary cylinder which is generally bored out eccentrically.

The improvements which form the subjectmatter of this invention consist, first, in the arrangement of one or more automaticallyacting steam-valves in the body of the pistonwheel, in combination with the slides, in such a manner that by the steam admitted to the interior of the cylinder a pressure is exerted on the inner ends of said slides, and thereby the pressure of the steam on the outer ends of the slides is counterbalanced 5 second, in combining with the piston-wheel a series of friction rollers and blocks held in position by annular grooves'in the cylinder-heads in such a manner that the friction created by the piston- Wheel is reduced to its minimum and an engine is obtained which works with the least possible loss of power from thatsource; third, in the arrangement of annular grooves in the heads'of the piston-wheel to receive corresponding projections rising from the sides of the quarters of said piston-wheel in such a manner that by said annular grooves the quarters are securely held in position and the screws which serve to fasten said heads to the quarters are relieved of a great portion of the strain to which they would otherwise be eX- posed; fourth, the combination, withone of the cylinder-heads, of avthin layer of Babbitts metal or other 'suitable composition, which is applied by casting it into the cylinder and rendered steam-tight by swaging, in such a man ner that said head can be moved slightly in and out without allowing the steam to escape, and that it can be set up close to the end of the piston-wheel and to the edge of the slides by a double set of screws, one set being applied to draw the head up and the other to force the same off from the flanges of the cylinder, and if the pistonwheel or slide wear out the fault can be readily corrected; fifth, in a double set of pipes extending from opposite sides of the cylinder up and branching off in two arms each, which terminate in a chamber or seat turned out to take a plugvalve with two sets of openings, one set to correspond to the upper branches and onesto the lower branches of the pipes leading from the cylinder,'in such a manner that by turningthe valve either of the branches can be made to perform the functions of steam supply and eX- haust pipe, and the motion of the engine thereby reversed with ease and facility.

A represents the cylinder, which is bored out eccentrically, as clearly shown in the drawings. The piston-wheel B is mounted on a shaft, C, which passes'freely' through ,openings c in the cylinder-heads b, and these openings are eccentric with the centers of said heads, so that the piston-wheel touches the inner circumference of the cylinder at the bottom part thereof, leaving a crescent-shaped space between its outer circumference and the inner circumference of the cylinder. Thebottom part of the inner surface of the cylinder, and also its top part, form segments of circles described from the center of the piston-wheel, v

and thereby a good bearing is provided for said piston-wheel at the bottom, causing the same to pack itself, and at the same time the slides D, which pass transversely through the piston-wheel, and which are intended to be constantly in contact with the inner circum ference of the cylinder, are not moved in or out while being exposed to the pressure of steam.

Said slides are forced apart by springs b bearing on their inner edges, and their sides are packed by strips o, which are let into cavities in the body of the piston-wheel, and which are held in steam-tight contact with the surfaces of said slides by springs d bearing on their inner sides, as clearly shown in Fig. l of the drawings.

In order to balance the pressure of the steam on the ends of the slides steam vis admitted tothe interior of the piston wheel through holes d', which are closed and opened by ball-valves e. These valves operate automatically as the piston-wheel revolves, and require no further attention.

The piston-wheel is provided with two heads, f, which are somewhat smaller than the body of the saine, and which extend through the openings a in the cylinder-heads, said openings being intended to form guides for the piston-wheel.

In order to reduce the friction between the heads f and their bearings the cylinderheads are provided with annular cavities g around the openings a, and these cavities are lled .with a series of friction-rollers, h, and intervening blocks i, as shown particularly in Fig. 3. Said friction -rollers project beyond the edges ofthe openings a, and form the bearings for the heads f, the blocks i being interposed simply to keep the rollers apart. The heads falso serve to keep togetherl the four parts or quadrants which constitute the piston-wheel, and between which the slides are fitted.

Screws 7' hold the heads in position, and in order to reduce the strain on these screws and prevent the quadrants from getting displaced an annular groove, g', is turned in each of the heads f, and these grooves are made to fit corresponding projections l, rising from the quadrants of the piston-wheel.

The quadrants of the piston-wheel are made precisely of the same width as the slides D, and they project beyond the heads f sufficiently to make bearing-surfaces, which work against the inner sides of the cylinder-heads b. One of these heads is screwed up tight against the iiange of the cylinder, but the other head is adjustable by means of a double set of screws, on m', one set being used to draw the head in and the other to push it out. By this arrangement the piston-wheel and slides can be made to work steam-tight against theinner surfaces of thefcylinder-head, and if the parts wear out the movable head can be readily readjusted; but in order to .prevent leakage of steam, it is indispensable that the cylindenhead shall be made to tit steamtight into the cylinder. This object, which would be very easily effected if the cylinder was bored out in a regular shape, is effected by casting on the cylinder-head, whilethe same is in its place, a thin layer, a, of Babbitts metal or other suitable materiah This layer is swaged or otherwise worked round the corner, so as to Aproduce a steanrtight joint and allow of moving the cylinder-head a short distance in or out with out permitting the steam to escape.

The cylinder A is provided with two holes, 0 o', in its circumference, on opposite sides of the piston-wheel, as shown in Figs. l and 3. From these holes emanate pipes p 19', each of which divides in two branches, gq* q gi, which extend from the main branches to the chamber F, the branches q q being on a level with the supply-pipe r, and the branches qi q* on a level with the exhaust-pipe s, both the steampipe and the exhaust-pipe passing through the side of said valve-chamber. This chamber is bored out to form the seat for the plug-valve G, which is provided with two sets of ports or openings, t t t* tit, one set being on a level with the steam-pipe r and the other with the exhaust-pipe s. 1f the valve is turned to such a position that the opening t registers with the branch pipe g', the aperture t will register with the steam-pipe r, the aperture t* with the branch pipe (1*, and the aperture t* with the exhaust-pipe s, and consequently steam will be admitted to the cylinder through the pipe p', and exhaust through the pipe p, the branch pipes q andq'* being closed, and the pistonwh eel turns in the direction of thearrow marked `on it in Fig. l. ABy reversing the valve the motion of the engine can be reversed at any moment, and in this case the branch pipe q will be in communication with the steam-pipe,

the branch pipe 'qit with the exhaust-pipe, and

the pipes q* q* q will be closed.

From the ports o o in the cylinder extend cavities c 'v in either direction to the circular` parts of the cylinder, allowing the steam which passes in through either oi' said ports to pass around the edge of the slide. Thesteam, therefore, will not begin to act on the pistonwheel until one of the slides has passed the cavity and entered the circular part of the cylinder above the piston-wheel, and it will begin to exhaust as soon as the slide leaves this circular segment. While being exposed to the pressure of the steam the slide will not move in or out, and all loss of power from that source is avoided.

It is obvious that this engine can be used for a rotary pump as well as for a steam-engine. Its operation is simple. It works with ,coinparatively little friction, and it is not liable to get out order.

- Having thus described our invention, we claim as new and desire to secure by Letters Patentf l. The valves o in the body of the pistonwheel B, in combination with the slides D, substantially as and for the purpose specified.

2. The friction rollers h and intervening blocks i, in combination with the heads f of the piston-wheel, and with annular grooves g in the cylinder-head, constructed and operatifng lsubstantially as and for the purpose set ort 5. The pipes p p', with branches gg* q q'i, in combination with the openings t t t* t* in the valve G, and with the valve-chamber F and steam and exhaust pipes r s, substantially as and for the purpose set forth.

SAM. G. HALL. GEO. W. BUGBEE. Witnesses:

E. J. CRossMAN, GEO. F. BALGH. 

